Psoriatic arthritis-related bone edema improves with anti-TNF therapy

Last Updated: 2007-07-23 14:52:18 -0400 (Reuters Health)

NEW YORK (Reuters Health) – Infliximab leads to significant improvement in bone edema associated with active psoriatic arthritis, a UK study of 18 patients indicates.

"Our results show resolution of bone edema at most sites regardless of location, and adds to the growing body of evidence confirming the efficacy and safety of infliximab in the treatment of psoriatic arthritis and skin psoriasis," writes the study team in the June Annals of the Rheumatic Diseases.

Bone-related changes contribute significantly to the morbidity and loss of function associated with psoriatic arthritis, explain Dr. Helena Marzo-Ortega of Chapel Allerton Hospital, Leeds, and colleagues.

Their study involved 18 patients, with a median age 41.5 years, who had skin psoriasis for a median of 20.3 years, and psoriatic arthritis for a median of 14.8 years. The patients were seronegative for rheumatoid factor and had joint swelling of the hand (12 patients) or knee (6 patients).

They were treated with infliximab (3 mg/kg infused at weeks 0, 2, 6, and 14) plus methotrexate. MRI of the affected joint was performed before and after treatment.

At baseline, bone edema was seen on MRI in 50% of patients (7 hands and 2 knees) in 30% of scanned joints, and this "improved or resolved" in all cases in the hand joints and in one knee joint at 20 weeks. MRI revealed a reduction in synovitis in 90%.

At week 20, infliximab therapy was also associated with a significant improvement in all clinical outcomes, including the Psoriasis Area and Severity Index, with a p value of 0.003, and the Psoriatic Arthritis Quality of Life index, with a p value of 0.006.

Eleven of 18 patients (65%) achieved an ACR response, of whom 45% had ACR70 or above and 54% had ACR20 or ACR50.

According to Dr. Marzo-Ortega and colleagues, "This is the first study to focus on bone edema in psoriatic arthritis and to show that edema seen on MRI improves significantly after anti-TNF treatment."

Ann Rheum Dis 2007;66:778-781.